WC涂层对40Cr密封体材料抗磨损性能的影响

Effect of WC Coating on 40Cr Steel Wear Resistant Performance of the Sealing Material

密封体材料在服役工况下易因磨损、腐蚀损伤而导致密封失效。采用在密封体表面制备耐磨涂层的方法可有效提高密封体的耐磨性能。本研究选用40Cr钢为密封体基体材料,WC陶瓷和Ni60+WC陶瓷为涂层材料,采用等离子喷涂的方法制备涂层材料,测试了涂层厚度、硬度,分析了涂层与基体材料的界面结合特性,对基体材料和涂层材料进行了两体磨损试验,分析了试验材料的磨损机理。研究结果表明:WC涂层和Ni60+WC涂层表面硬度高,涂层厚度均超过1 000μm,且与基体间结合良好;与基体40Cr相比较,两种涂层在销盘磨损试验中因高硬度WC陶瓷的存在表现出良好的耐磨性,WC涂层磨损抗力是40Cr基体的1.9倍,Ni60+WC涂层磨损抗力是40Cr基体的2.5倍,且Ni60+WC涂层因含金属Ni致使涂层脆性降低,耐磨性最优。

The sealing body materials under service conditions were easily led to seal failure by wear, corrosion damage. The preparation of wear resistant coating of the seal body system can effectively improve the wear resistance of the sealing body. In this paper, 40Cr steel is selected as the sealing body base material, WC ceramic and Ni60＋WC ceramic coating material have been prepared by plasma spraying. The thickness and hardness of the coating were tested, and two body abrasion tests were carried out on the substrate material and the coating materials. Analysis of the coating and substrate interface bonding properties and wear resistant mechanism of test material were done. The results show that there have high surface hardness of WC and Ni60＋WC coatings, and the coating thickness all are more than 1 000 p,m, interface bonding with the matrix are good. Compared with matrix 40Cr, two kinds of coatings on a pin-on-disk wear testing because of the high hardness of WC ceramics show good wear resistance, abrasion wear resistance of WC coating is 1.9 times than that of 40Cr matrix, Ni60＋WC coating wear resistance is 2.5 times of 40Cr matrix. For containing Ni, the Ni60＋WC coating brittleness decreases, but the wear resistance is optimal.